Ultrahigh-pressure phases of H(2)O ice predicted using an adaptive genetic algorithm

TitleUltrahigh-pressure phases of H(2)O ice predicted using an adaptive genetic algorithm
Publication TypeJournal Article
Year of Publication2011
AuthorsJi M, Umemoto K, Wang CZ, Ho KM, Wentzcovitch RM
Journal TitlePhysical Review B
Volume84
Pages220105
Date Published12/13
ISBN Number1098-0121
Accession NumberISI:000298114200002
Keywordsmolecular-dynamics, planets, water
Abstract

We propose three phases of H(2)O under ultrahigh pressure. Our structural search was performed using an adaptive genetic algorithm which allows an extensive exploration of crystal structure at density functional theory accuracy. The sequence of pressure-induced transitions beyond ice X at 0 K should be ice X -> Pbcm -> Pbca -> Pmc2(1) -> P2(1) -> P2(1)/c phases. Across the Pmc2(1)-P2(1) transition, the coordination number of oxygen increases from 4 to 5 with a significant increase of density. All stable crystalline phases have nonmetallic band structures up to 7 TPa.

URL<Go to ISI>://000298114200002
DOI10.1103/Physrevb.84.220105
Alternate JournalPhys Rev B